The notion that lightning always strikes the tallest object is actually a myth. The path of a lightning bolt is actually purely random, and like any other form of electricity, tends to seek the path of least resistance, which is not necessarily the tallest object. For example, an antenna mounted on a chimney may present a higher-resistance path than an air terminal of a lightning rod system mounted at a lower height. In which case, since the air terminal will provide a lower-resistance path, it will safely channel the energy from the lightning bolt to the ground.
Also, the majority of cloud-to-ground lightning strikes actually tend to originate from the ground since the rain water carries electrons from the clouds to the ground, causing the ground to become negatively charged and the clouds to become positively charged. Since the flow of any electrical current is from negative to positive (electrons move from where there are more to where there are less), the bolt will actually jump from the ground through the path of least resistance to the cloud above.
But, as was stated earlier, a bolt of lightning that travels over a mile through the air will not be stopped by a few inches of rubber in the tires.